The effect of too much intravenous lidocaine on bispectral index.

Systemic local anesthetics have beneficial perioperative properties and have an anesthetic-sparing effect. To assess depth of anesthesia during lidocaine infusion, it would be important to know the effect of systemic local anesthetics on bispectral index (BIS). However, this has not been investigated. We report an inadvertent overdose of i.v. lidocaine in a patient monitored with BIS. BIS decreased to 0 for approximately 15 min, indicating that lidocaine and sevoflurane interact to decrease BIS.